Attachment for tractors and the like



Sept. 5, 1939. H. A. Hurcl-nNs 2,171,792

ATTACHMENT FOR TRACTORS AND THE LIKE Filed Jan. 27, 1937. 3 Sheets-Sheet l @Aww/- V .Hs/92130,@

Sept. 5, 1939. H. A. Hu'rcHlNs ATTACHMENT FOR TRACTORS AND THE LIKE 3 w u y@ Z e @c .WW

fm e Patented Sept. 5, 1939 UNITED sTATEs PATENT OFFICE ATTACHMENT FOR TRACTORS AND THE LIKE 14 Claims.

This invention relates to attachments for tractors, trucks and the like, and relates more particularly to a power take-01T or power unit to be applied to a tractor for the purpose of operating and controlling a bulldozer and other equipment carried and drawn by the tractor. A general object of this invention is to provide an improved, simplified and particularly eiective power takeoi or power unit of the character referred to.

Another object of this invention is to provide a power take-oil? attachment for a tractor or truck embodying vertical line operating drums rotatably supported from their lower ends. In accordance with the present invention the drums of the unit are dependably supported without the necessity of employing a support at their upper ends, as has been the general practice heretofore, 'whereby the unit is cheaper, lighter in weight, and easier to service than the power units heretofore introduced.

Another object of this invention is to provide a power unit or attachment of the character mentioned in which the clutches andthe brakes for governing the drums are at the upper ends of the drums where they maybe relined and repaired without disturbing the drums and where they do not accumulate grease etc. which may interfere with their operation.

Another object of this invention is to provide a practical power take-01T unit for a tractor or the like having novel means for rotatably supporting the drums on a single housing in a manner so that the strains are imposed on the drums immediately adjacent the main casting of the housing.

Another object of this invention is t0 provide a power take-oi or power unit of the character mentioned in which the wear resulting from the rotation of a line operating drum is taken by a single simple tubular part that may be easily reground or replaced and by replaceable bearings engaging the tubular part.

Another object of this invention is to provide a power take-off unit of the character mentioned embodying novel means for controlling the brakes of the winding drums.

Another object of this invention is to provide a power take-oil unit of the character mentioned that embodies a very simple and compact drivefor the drums.

Another and important object of this invention is to provide a power take-0E or power unit of the character mentioned in which the linesfor operating the equipment at the front of the tractor are guided forwardly from the rear portion of the tractor' by sheaves carried by leaf-springs capable of flexing in any direction as required. The leaf-springs carrying the line guiding pulleys are simple, inexpensive and easily replaced and are just as effective as the heavy complicated 5 and expensive pivoted arms heretofore employed to carry the line guiding sheaves.

Another object of this invention is to provide a tractor attachment of the character mentioned in which the strains resulting from the use or operation of the bulldozer or equipment at the front of the tractor are equally distributed on two lines, as distinguished from former attachments having a single line taking all the loads and strains. 15

A Another object of this invention is to provide an attachment or power unit of the Ycharacter mentioned embodying means for individually adjusting or taking up the two lines just reerred to.

Another object of the invention is to provide an improved power take-oir unit of the character mentioned in which no guide sheaves are required for the lines employed to operate equipment drawn by the tractor.

A further object of this invention is to provide an improved and practical power unit of the character mentioned that is compact, light in Weight, and inexpensive, and that is strong and durable.

'Ihe various objects and features of my invention will be fully understood from the following detailed description of a typical preferred form and application of my invention, throughout which description reference is made to the ac- 35 companying drawings, in which:

Fig. 1 is a top or plan view of the unit or attachment provided by the present invention showing it in position on a typical tractor which appears in broken lines. Fig. 2 is a side elevation 40 of the tractor and attachment illustrated in Fig.

1. Fig. 3 is an enlarged sectional View taken as indicated by line 3-3 on Fig. 2 and illustrating the means for adjusting one of the lines. Fig. 4 45 is a vertical detailed sectional view taken as indicated by line 4--4 on Fig. 3. Fig. 5 is an enlarged vertical detailed sectional view of the )power unit proper with a portion of one of the drums appearing in side elevation and a portion 5o of the said drum broken away, being a view taken as indicated by line 5-5 on Fig. 2. Fig. 6 is a top or plan view of the power unit proper illustrating the parts in the neutral position, and Fig. 7 is a fragmentary front elevation of the 5I power unit illustrating the adapter and power take-olf shaft in vertical cross section. 4

The device or attachment provided by this invention is adapted to be employed on tractors and thelikc of various sizes, makes and types, and is operableto control and operate grading and excavating equipment and devices of various natures. In the following detailed disclosure I will describe a typical embodiment of the invention as employed on a typical tractor to control oroperate a bulldozer, it being understood that the invention is not to be construed as limited or restricted to the specific form or application of the invention about to be described.

The details of the tractor T illustrated in broken lines are omitted from the present description as they form no part of the present invention. The bulldozer' I0 is of the angling type and is provided with a supporting frame having members at the opposite sides of the Vtractor T. The frame members II of the bulldozer are pivotally connected lat I2 with the tracks of the tractor. The members II areprovided with forwardly and inwardly extending parts I3 joined at the front of the tractor. The bulldozer I I) is pivotally connected with the joined parts I3 at I4 so that it may be swung to various angular positions. r[he frame members II being pivotally supported at their rear ends allow the bulldozer to be raised and lowered relative to the ground level. Links I5 are pivotally connected. to the bulldozer I0 adjacent its opposite ends end extend rearwardly to the frame members II. Removable pins or bolts I6 secure the rear ends of the links I5 to the frame members II. The pins I6 are insertable in longitudinally spaced openings I1 in the frame members II to 'provide for the proper supporting of the oppos-ite ends of the bulldozer when it is swung to various angular positions. The bulldozer described above may be considered as typical of the "type of equipment that may be operated by the attachment of the invention. The power take-off or attachment of the invention is operableto raise and lower the bulldozer I0 relative to the ground level.

The powertake-oi or attachment of the present invention provides, generally, a unit U at the rear end of the tractor T, comprising a housing 20, a pair of drums `2| rotatably carried by the housing 20. a drive 22 in the housing 20 for rotating the drums 2|, clutches 23 and brakes 24 lor controlling'the drums 2| and means 25 for operating the clutches and brakes, lines 26 operated by a drum 2| of the unit U and means 2.' guiding the lines 26 to the bulldozer `I0 to operate the same.

The unit is intended to be mounted at the rear end of the tractor T to be driven by the usual power take-off shaft 28 provided on the tractor. The unit U may be convenientlylocated for `the control and operation of the equipment drawn by the tractor T as well as the bulldozer I0 or other equipment at the front of the tractor. The housing 20 of the unit U is characterized by its simplicity and eompactness. The housing 20 ini-Indes a hollow substantially horizontal body 29 havingl spaced upper and lower walls 30 and 3|. respectively. The opposite ends of the hollow body 29 have access openings closed by suitable bolted on caps or .covers 32. The intermediate portions of the body walls 30 and 3| are bowed or curved upwardly and downwardly, respectively,I to provide the housing body 29 with an enlarged intermediate portion 33. The rear end of the enlarged body portion 33 is closed by a removable plate 34.

A substantially vertical flange 35 is provided on the forward end of the enlarged portion 33 and is bolted on an adapter 36. The adapter 3S is in turn bolted or otherwise secured to the frame of the tractor T to mount the unit U on the tractor. The adapter 36 is provided to facilitate the easy mounting of the unit on the tractor T and of course may be varied for application to tractors of various makes, types, etc. The housing 20 is mounted where the enlarged portion 33 of its body 29 is longitudinally aligned with the power take-olf shaft 28. The flange 35 projects `upwardly from the adapter 36 for the purpose to be hereinafter described. The upper and lower walls 3D and 3| are provided with vertically aligned openings 38 and 39, respectively. A pair of aligned openings 38 and 39 are spaced from each side of the longitudinal center of the housing 20, said pairs being equally spaced from said center. The housing is adapted to contain lubricant and a suitable lubricant admitting fitting 40 may be provided on the plate 34. An opening 4I is provided in the lower wall of the enlarged housing portion 33 to provide for the draining of lubricant from the housing and is normally closed by a plug 42.

The housing 20 further includes two spaced substantially vertical parts 43 which I will term housing extensions. The housing extensions 43 are tubular and are alike in size and shape. The lower end portions of the housing extensions 43 are received in the openings 38. Flanges 44 on the extensions 43 are bolted to the upper wall 30 of the housing body 29 to secure the extensions to the body. Each housing extension 43 has an annular upwardly facing shoulder 45 adjacent and above its securing flange 44. A thrust nut 46 is provided on the upper end portion of each housing extension 43. The extensions 43 rotatably support the drums 2| as will be hereinafter described and their peripheries may be machined adjacent the shoulder 45 and the nuts 4B. The openings 39 in the lower body wall 3| are closed by removable plates 41. The plates 4'I may be provided with annular Aflanges 48 projecting upwardly into the housing body 29 to oppose the lower ends of the extensions 43. It will be observed that the housing 20 is very compact and is characterized by the single integral body casting 29 which requires a minimum of machining.

The drums 2| are provided to operate the lines 26 and other lines that may be required for the control and operation of equipment on or drawn by the tractor T. In accordance with the invention the two drums 2| may be identical, as illustrated. The drums 2| are tubular and each drum 'surrounds a housing extension 43 with suitable clearance. Annular oppositely facing thrust shoulders 49 are provided on the interiors of the drums 2| adjacent their opposite ends. Suitablev bearings 50 rotatably support the inner or lower ends of the drums 2| on the extensions 43 and operate between the thrust shoulders 45 and 49. Similar anti-friction bearings 5I rotatably support the upper portions of the drums 2| on the housing extensions 43 and operate between the nuts 46 and the upper shoulders 49. It is to be .noted that the drums 2| are mounted close to the body 29 ofthe housing 2|) and adjacent the vertical plane of the power take-on shaft 28.

Relativewide end flanges 52 are provided on the drums 2| to guide the lines and to prevent displacement of the lines from the drums. An opening 53 may be provided in the lower flange 52 of each drum 2l to receive the .end portion of a line which is to be secured to the drum and wound thereon. Bolts 54 may be threaded in openings in the lower flanges 52 adjacent the openings 53 to operate spring clamps 55 for gripping the end portions of the cables. A stud or hook 56 is provided on the periphery of each drum 2| midway between its end flanges 52 to facilitate the connection of the lines with the drums as will be hereinafter described. It is to be understood that other means may be employed to associate the cables or lines with the drums 2|, if desired. A plurality of spaced openings 51 is provided in the upper ange 52 of each drum 2| to allow dirt and foreign matter to escape from the clutches 23, as will be subsequently described.

The drive 22 for operating the drums 2| includes a drive shaft 58 in the enlarged central portion 33 of the housing 20. The shaft 58 is rotatably supported by suitable bearings (not shown) in the housing and adapter 36 and is intended to be connected with the shaft 28 by a spline or key connection in the well known manner. A worm 59 is keyed or otherwise xed to the shaft 58 to operate in the portion 33 of the housing 20. The drive 22 further includes a rotatable and longitudinally shiftable sleeve 60 extending longitudinally through each housing extension 43. The sleeves 68 extend downwardly into the housing body 29 and their lower portions l carry worm wheels 6| The worm wheels 6| mesh with the worm 58 and are slidably keyed or splined on the sleeves 60. The lower ends of the housing extensions 43 and the flanges v48 are present at the opposite sides of the worm wheels 6| to prevent vertical displacement of the wheels and to take end thrusts from the wheelsiil-` The sleeves 65 driven or rotated by the gearing just described drive their respective drums 2| through the clutches 23.`

The invention provides improved and particularly long wearing means for rotatably-supporting the sleeves 6|). A normally stationary shaft 62 extends longitudinally through each sleeve 60. The lower ends of the shafts 62 may be supported on the plates 41. In the particular structure illustrated the shafts 62 have tapered portions 63 litting correspondingly tapered openings 64 in the plates 41. Nuts 65 are threaded on the shafts 62 to clamp against the plates 41 and hold the shafts against rotation and longitudinal movement. The lower end portions 66 of the shafts B2 are polygonal to be readily engaged by a wrench or turning tool for turning the shaft when the nuts 65 are loosened. The means for rotatably supporting the sleeves 6|! include bushings 61 on the shafts 62 extending through the lower end portions of the sleeves. The bushings 61 effectively support the lower ends of the sleeves which carry the worm wheels 6|. The lower ends of the bushings 69 may bear on the plates 41 while the upper ends of the bushings may engage shoulders 68 on the shafts 62. "I'he shafts 62 project upwardly beyond the upper ends of the housing extensions 43 to form elements of the-means for operatingrthe clutches 23 as will be hereinafter described. The means for supporting the sleeves 6D further include bushings 69 in the upper end portions of the housing extensions 43. The bushings 69 rotatably and shiftably support the upper portions of the sleeves 68. 'Ihe bushings 69 may bear downwardly on shoulders 10 on the interiors of the housing extensions 43. If desired, cover plates 1| may be provided at the upper ends of the drums 2| to prevent the entrance of dirt and foreign matter to the interiors of the drums and the housing extensions 43. The sleeves 60 may be continuously rotated by the drive 22 to rotate the drums 2| through the medium of the clutches 23.

A clutch 23 is provided for controlling each line operating drum 2|. It is a feature of the invention that the clutches 23 are located at the upper ends of their respective drums. Each clutch 23 includes a part rigid with a drum 2| and a part rgid with its related sleeve 60. Each clutch includes an annular or tubular flange 1| integrally joined with the upper flange 52 of a drum 2| through the medium of a brake drum 12. In practice circumferentially spaced webs 13 may connect the clutch flanges 1| with the brake drums 12. The internal surfaces 14 of the flanges 1I are pitched or conical. Each clutch further includes a hollow cone 15 within its flange 1|. The cones 15 have their lower ends secured to radial flanges 16 on the upper ends of the sleeves 60. Friction material or lining 11 is provided on the outer surfaces of the cones 15 to cooperate with the surfaces 14. It will be apparent how cooperation of the lining 11 with the surfaces 14 transmits rotation between the sleeves 60 and the drums 2|. The cones 15 of the clutches 23 are rigidly connected with the sleeves 60 lto move longitudinally therewith and upward movement of the sleeves may release the clutches to free the drums 2| Cover plates 18 may extend across the upper ends of the clutch cones 15 and the upper ends of the clutch flanges 1|.

The brakes 24 are provided to prevent rotation or backing up of the drums 2| when the clutches 23 are released and thus operate to retain the bulldozer I0 or other equipment operated by the power take-olf in any one of the possible operating positions. Each brake 24 includes a brake drum 12 referred to above. The drums 12 may be integral tubular extensions of the upper flanges 52 of the winding drums 2|. The brakes 24 further include flexible brake bands 19 extending around the drums 12 and carrying friction material or lining 80 for cooperating with the flanges. A bracket 8| is secured to the flange 35 of the housing 20 and its opposite ends are provided with spaced lugs 82. Pins 83a are carried by the lugs 82 and each pin pivotally connects one end of a brake band 19 with the relatively stationary bracket 8|. The other ends of the brake bands 19 are connected with control parts of the means 25 as will be hereinafter described.

The means 25 are conveniently operable by the operator of the tractor T to control the clutches 23 and the brakes 24. Each means 25 is operable to engage the clutch 23 of one of the drums 2| to cause rotation of the drum and is also operable to simultaneously disengage the clutch 23 and release the brake 24 to leave the drum 2| in a free spooling condition. Each means 25 includes a nut 83 threaded on the upper end portion of a shaft 62. The nuts 83 may be relatively long and capable of extensive threading movement along the shafts 62. The threads of one nut 83 are righthand threads and those of the other nut 83 are lefthand threads. In accordance with the invention the cones 15 of the clutches 23 are associated with the nuts 83 to move vertically or longitudinally therewith and to freely rotate thereon. f-Each cone carrying flange 16 has a tubular boss or hub 84 surrounding a reduced lower portion of a nut I3. Bearings Il within the bosses I4 engage about the nuts I3. The bearings I5 are thrust bearings and act between nuts I5 and shoulders I1, on the nuts I3 whereby the cones are movable longitudinally with the nuts I3. Suitable cover plates II may be provided on the upper ends of the hubs I4. The nutsl I3 project upwardly beyond the cover plates 1I.

Each means further includes collars II and II adjustably fixed to a nut I3. The collars II and II may be split and normally clamped on the nuts I3 by bolts Il. Each collar II carried an operating lever I2. The levers I2 project upwardly and forwardly to have handle portions disposed at the opposite sides of the operators seat S of the tractor T. It will be apparent how swinging of the levers I2 is operable to turn the nuts I3 to thread them along the staonary shafts I2 to effect longitudinal movement of the clutch cones 15. lThus the turning of a lever I2 in one direction engages one of the clutches 23 and swinging of the lever in the other direction disengages the clutch. A spring I3 extends between lugs I4 on the collars IIto yieldingly urge the levers I2 to the positions where the clutches 23 are released or disengaged.

Each means 25 further includes camsor levers ss pivoted onine pins w. 'me 1evers ss.

may have spaced arms II pivotallysupported on the pins I3. The levers I5 extend from the pins I3 in the general direction of the longitudinal axis of the related drum assembly. '111e arms I3 carry pivot pins I1 which pivotally connect the levers with the movable ends of the brake bands 1I. The relationship of the pivotal mountings of the ends of the brake bands 1I is such that rotation of a drum 2I in one direction causes the related band 1I to wrap or tightenon the brake drum 12 while rotation of .the drum 2| in the line tensioning direction merely causes Adragging of the brake band 1I. Spring means is provided to yieldingly urge the two levers I5 toward the positions where the brakes 24 are set or operative. In the structure illustrated pins II project from the rear portions of the levers I5 and a spring II extends between and connects with the pins II to urge the levers I5 inwardly or toward one another.`

It is a feature of the invention that means are provided to hold the brakes 24 and the clutches 23 in the free-spooling positions or released positions when this is desired by the operator. Arms III project forwardly from the collars II. The arms III are yoked at their outer ends to carry rotatable rollers III. The rollers III are adapted to cooperate with the above described toggle le? vers I5. A notch II2 is provided in the rear edge or side of each lever I5. The notches II2 are adapted to receive the rollers III. Rounded projections III are provided on the rear sides of the'levers I5 immediately forward of the notch II2. The parts are related so that the rollers III are clear of or out of active engagement with the related levers I5 when the clutches 23 are engaged. When an operating lever I2 is moved to the position where the related clutch 23 is disengaged the roller III is still clear of the related lever I5. `The roller III may engage the projection II3 when the clutch 23 is in the released position but the roller III does not roll over the 'projection unless the operator deliberately applies considerable force to` the proper operating lever I2 to effect this movement. In other words the projection III is operable to prevent unintentional engagement of the 'roller m with the ad'- jacent notch II2. When the operator wishes to have a completely free spocl or drum 2| he operates the proper lever I2 to a position where the roller III rolls over the projection III into the notch II2. This operation moves the roller III .past or over the center line extending between the pivotal axes of the lever I5 and the arm IIII so that cooperation of the roller III with the notch II2 resists the action of the spring II to return the released clutch 23 to the engaged position. When a roller III is engaged in a notch II2 the brake I4 of the related drum assembly is released and the clutch 23 is disengaged providing a free spool or drum. It will be observed that this free condition of the drum 2I is only obtained when the operator intentionally swings a lever I2 to engage a roller III in a notch II2. When a roller III is engaged in a notch I I2 the lever I5 and the adjacent arm IIII form toggles to resist the spring II and positively hold the brake 24 and the clutch 23 released until the operator deliberately or forcibly swings the roller III out of the notch II2 by operation of the proper lever I2. While the action of one of the means 25 has been described above it is to be understood that the operation of the two means 25 is the same except that their levers I2 are swung in opposite directions as will be readily understood.

Separate cables or lines may be operated by the drums 2I for the control and operation of equipment drawn by the tractor T. When the unit U is employed for this purpose the lines are wolmd on the two spools 2| to pass from their inner sides or their sides closest to the longitudinal center line of the tractor T. This arrangement of the lines is important as no guide sheaves are necessary to guide the lines leaving the drums 2I immediately adjacent the center line of the tractor. It is believed that it will be readily understood how the drums 2l of the unit ,U may be employed to control and operate various clases of equipment that may be drawn by the tractor T.

The lines 2I illustrated in the drawings are provided to operate or control the bulldozer II at the forward end of the tractor T. When the lines are employed for this purpose they may both be wound on one drum 2l Aas illustrated, so that one line 25 passes laterally from the front of the drum and the other line 25 passes laterally from the rear of the drum. .In practice the two' lines 2I may form parts of a single length of cable wound on the drum 2I and secured to the drum intermediate its ends. 'Ihe cable constituting the lines 25 may have a loop or eye |05 engaged over the hook 5I on the drumn2l which is emplayed for the operation of lines. With the lines 2I arranged as just described rotation of the drum 2I in one direction spools in both lines 26 while rotation of the drum in the other `plays out both lines.

The means 21 for directing or guiding the lines 25 is an important feature of the present invention. The means 21 includes a guide pulley or sheave III for guiding the line 26 that passes from the front of the drum 2I and a similar sheave II'I for guiding the line 25 that passes laterally from the rear side of the drum. The invention provides novel and particularly effective means for supporting the sheaves I 06 and III1 where they direct or guide the lines 2G to extend forwardly at opposite sides of the tractor T. This means comprises a leaf spring |08 secured 'substantially parallel relation tothe line 26 passing from the forward side ofthe drum 2|. The spring |09 has its inner end bolted to a boss on the rear side of the housing 20 adjacent the drum 2| carrying the lines 26. The spring |09 extends outwardly or laterally from the boss in substantially parallel relation to the line 26 `passing from the rear side of the drum 2|. The sheave |06 is secured to the outer end of the spring |08 by a suitable bracket ||2 and the sheave |01 is secured to the outer end of the vspring |09 by a similar bracket ||3. The bracki |06 and |01 in the proper incline or angular positions.

Thesprings |08 and |09 are adapted to flex to permit all necessary movement of the sheaves |06 and |01 during the operation of the tractor T and the bulldozer |0. It will be noted that the springs |08 and |09 are simple, inexpensive and light in weight, and are easily replaced.

The means 21 further includes line guiding tubes ||4 secured to the sheaves |06 and |01 or the Vsupports of the sheaves and extending forwardly vand upwardly to adjacent the front end of the tractor. The tractor is provided at its opposite sides with a pair of spaced upwardly and forwardly extending boom-like arms ||5. The arms ||5 are carried by the tracks of the tractor in any typical manner. A horizontal shaft ||6 extends between the forward ends of each pair of arms ||5. The forward ends of the tubes 4 are supported on the shafts ||6 by suitable bearings ||1. The lines 26 extend from the guide sheaves |06 and |01 and pass forwardly through the tubes ||4 to the shafts H6.

Systems of sheaves are provided on the shafts ||6 and the bulldozer |0v and the lines 26 operate over the systems of sheaves and have their dead ends fixed to the shafts I6. It will be apparent that the lines 26 may be compounded as desired --by providing sheave systems with as many sheaves as required. In the case illustrated there .are two sheaves |8 on each shaft ||6 and twoA sheaves |29 on each part 3 of the bulldozer I0 for the compounding of the lines 26. The sheaves |28 may be carried by suitable bearing brackets |9 on the bulldozer parts I3. The lines 26 pass from the second or last sheaves |28 back to the shafts ||B where their dead ends are normally fixed.

The invention provides novel means fox adjusting or taking up the dead ends of the lines 26. Take-up spools |20 are rotatable on vthe shafts H6' and the dead ends of the lines 26 are wrapped on and suitably fixed to the spools |20. The outer ends of the spools |20 are provided with circumferential series o f ratchet teeth |2I. Ratchet dogs |22 are pivoted to the adjacent arms ||5 and cooperate with the ratchet teeth |2| to normally prevent rotation of the take-up spools |20 against the strains or turning forces imposed on the spools. Suitable means are provided to effect rotation of the take-up spools |20. In the case illustrated circumferentially spaced openings |23 are provided in the spools |20 to receive a rod or turning tool for turning the spools. By manipulating or turning the take-up spools |20 the individual lines 26 may be adjusted and the lines may be individually wrapped on' the take-up spools |20 to remove slackness from the lines whereby they operate in the desired manner. It will be noted that the strains resulting from operation ofthe bulldozer |0 are equally divided between the two lines 26 which are connected with the bull-dezer I0 at points equally spaced from its center. In the event that slackness develops in a line 26 it may be` readily removed by rotating the take-up spool |20 to remove the slackness.

In operation it may be assumed that the engine or prime mover of the tractor T is continuously operating to rotate the shaft 28. The drive 22 accordingly continuously rotates the sleeves 60 and the clutch cones 15 secured to the sleeves. When the drums'2l are idle the operating levers 92 are in positions where the clutches 23 are released and Where the brakes 24 are set or operative. The brakes 24 operate to normally prevent rotation of the drums 2| in the unspooling direction. Assuming that the lines 26 are wound on one of the drums 2| and are operatively connected with the bulldozer I0 as illustrated,4

bring the lining 11 in active engagement withl the surface 14. As the cone 15 is continuously rotating the engaging of the clutch 23 results in rotation of the drum 2| in a direction to wind in the lines 26. During this rotation of the drum 2| the brake 24 is inoperative, that is, it does not materially resist rotation of the drum in the line spooling direction. When the drum 2| is rotated to take in the lines 26 the lines of course raise the bulldozer I0. The springs |08 and |09 support the sheaves |06 and |01, respectively, to properly guide the lines 26 and yet allow the necessary shifting of the sheaves when the tractor is in operation.

When the bulldozer i0 has been raised suiciently the operator moves the proper lever 92 to turn the nut 83 and thread it upwardly on the shaft 62 to disengage the clutch 23. Immediately upon disengagement of vthe clutch 23 the brake 24 sets or operates. As described above, the brake 24 is of the wraparound type that automatically grips or engages when the drum 2| tends to turn in the unspooling direction. Thus the brake 24 operates to hold the drum 2| against rotation -and operates to hold the bulldozer I0 in the rai-sed position.

To lower the bulldozer l0 the operator swings the proper lever 92 to bring the roller |0| into active engagement with the adjacent lever 95. The roller |0| is operable to act on the lever 95 or its projection |03 to swing the lever to a position where the brake 24 is released. This action of the roller |0| is accompanied by turning of the nut 83 in a direction to disengage or further disengage the clutch 23. With the brake 24 and the clutch 23 both released, the weight of the bulldozer I0 and the load carried thereby, if any, causes downward swinging of the bulldozer and unreeling of the lines 26 from thev drum 2|. Lowering of the bulldozer |0-may be stopped at any point by swinging the proper lever 92 to the v position where the roller |0| disengages from the adjacent lever 95, whereupon the spring 99 automatically swings the lever 95 to re-engage the brake 24. The brake band 19 thereupon automatically wraps onto its drum 12 to stop rotation of the drum 2|. If it is desired to leave the brake 2l and the clutch 23 in the released condition for any substantial period, the operator merely swings the proper lever 92 tothe position where the roller |0| engages in the notch |02 of the adjacent lever 05. With the parts in this position the brake 24 is held released and the clutch 23 is in its released position so that the bulldozer |0 may rest on 'the ground.

It is to be understood that the drums 2| of the unit U maybe individually controlled and operated simultaneously by the two control means 25 to-eifect the desired or necessary operation of.

lines operated by the drums.l 'I'hus when the unit U is employed vto operate equipment drawn `by the tractor it maybe desirablel to take up.

the line on one .drum 2| and allow it to unspool from the other drum 2|. 'Ihe clutches 23fmay l be-adjusted by loosening the nut l5 and then turning the shafts 02-byvmeans of the polygonalv portions 60. This rotation of the shafts 62 resultsin-threading. of the nuts I3 and adjustment of the clutch cones relative to the anges 1|.

The drums 2| .are located at opposite sides of thelongitudinal 'center line oi' the tractor and the lines may pass rearwardly from the drums immediately adjacent said center line so that no guide 1 sheaves are required for the lines when the uni U is employed to control or operate apparat drawn by the tractor. The unit U embodying the two` drumfassemblies supported at their lower ends only is very small, compact and light in weight. The lines pass from the .drums 2| adja-v cent the housing 20 to impose minimum strains on the housing and the other parts. Further, the supporting of the drum assemblies at their lower ends leaves their upper ends free to receive th clutches 23 and vthe various elements of the controls 25. Ihe clutches 23 being above the drums 2| do not accumulate grease, etc., that 2| and the other parts may be easily removed for l() may interferefwith their operation.A The drums 2| and the parts connected therewith are dependably and effectively supported.

The driving sleeves 00 are internally supported at the upper ends of the drums 2| bythe bushings 69. The sleeves which receive practically all the wear resulting from rotation of the drums re-grinding or replacement. The single integralhousing body 20 requires a minimum of machining andvyet is such that the parts of the drive 22, the sleeves 60 and. the various other parts may be removed from it'when necessary.

When the apparatus is employed for` the control and operation ofthe bulldozer I0 the means 21. guides the lines 26 so-that two lines operated by a single drum 2| assume -equalloads The lines 26 extending forwardly to theopposite sides of the tractor are associated with the bulldozer I0 through the above-described systems of sheaves IIB and |20 to raise or operate the bulldozer at points spaced from its center and under the control of the single drum. The lines 26 may be adjusted or taken up at any time by means of the take-up spools |20 so that the forces on the lines 26 may be maintained equal at `all times.- The springs |08 and |09 are important as they assure the proper supporting of the guide sheaves |06and |01 and allow the required movement of thesheaves. 'I'he springs |00'and |09 are small and light in weight and may be easily and inexpensively replaced when necessary.

of the following claims. v

, Having described my invention, I claim 1. A power take-on unit for a-tractor or truck to those skilled in the art or fall within the scope comprising, a housing carrying an upwardly projecting tubular part, a rotatable drum above the housing supported by said part. and a drive for the drum including a shaft extending from the housing through said part, and a clutch above the drum for transmitting rotation from the shaft .l

to the 2. A power'take-off unit for a tractor or truck comprising, a supporting structure to be attached to the. tractor, a tubular part rigid with and pro- `iecting upwardly from the structure, a drum above vthe' structure rotatably-supported on said part, a rotatable member extending from 'the l'structure `and passing upwardlylthrough the said part, 'a drive 'for rotating the member,v and a clutch vabove the drum fortransmitting'rotatlon from the member to the drum. 3. A power take-olf unit-for a tractor or truck comprising, a housing having-an extension projecting from its upper side, a drum rotatable on theextension. a rotatable member extending through the extension, a drive in the housing-'ro tating the member, and a clutch above the druml for transmitting rotation from the member to the comprising, a 'housing having an extension pro- "jecting from itsk upper side, a `drum rotatablev on the extension, a rotatable member extending 4.' A power take-olf unit for a'tractor or truckV above the drum Afor transmitting rotation from theA member to the drum.

5. -A power take-oil' unit for a tractor comprising,'a housing having an extensionprojecting from its upperside, a drumrotatable on the ex-v tension,arelatively stationary shaft carried by the housing to extend upwardly through. theexbly supported bythe shaft and extension, a clutch at the upper end of the extension for transmitting tension, a rotatable sleeve on the shaft exrotation between the sleeve and ythe drum, and

a drive in the housing for rotating the sleeve.; 6. In a powertake-oil' attachment for atractor, a housing to be attached to the tractor, an

upwardly projecting tubular extension on the housing, a drum rotatable on the extension, a

driven member extending upwardly through the extension, and a clutch at the upper end'of the extension for transmitting rotation from the member to the drum;

7. Ina power take-off attachment'for a tractor, a housing to be attached to vthe tractor, an upwardly projecting tubular extension on the housing, a drum rotatable on the extension, a longitudinally shiftable and rotatable member extending through the extension, a clutch part on the upperA end of the drum, a clutch part on the member engageable with the first named part uponlongitudinal movement of the member, and meansfor effecting longitudinal movement of the member.

8. In a power take-off attachment fora tractor, Aa housing to beattached to the tractor, an upwardly projecting tubular extension on the housing, a drum rotatable on the extension, a tubular rotatable and longitudinally Vshiftable member extending through the extension, a drive in the housing for rotating the member, a clutch part on the upper end of the drum, a clutch part on the member engageable with the first named part, and means at the upper end of the member for moving the same longitudinally.

9. In a power take-off attachment for a tractor, a housing to be attached to the tractor, an upwardly projecting tubular extension on the housing, a drum rotatable on the extension, a tubular rotatable and longitudinally shiftable member extending through the extension, a drive in the housing for rotating the "member, a clutch part on the upper end of the drum, a clutch part on the member engageable with the first named part, and means at the upper end of the member for moving the same longitudinally, said means including a relatively stationary shaft extending through the member, and a nut threaded on the shaft to shift the second mentioned clutch part.

10. In a power take-off attachment for a tractor, a tubular support, a winding drum rotatable on the support, a tubular rotatable and longitudinally shiftable member extending through the support, a stationary shaft extending through the member, means for rotating the member, a brake drum on the winding drum, a clutch part on the winding drum, a clutch part on the member cooperable with the first named clutch part, a nut threaded on the shaft for shifting the second mentioned clutch part, a band for cooperating with the brake drum, means urging the band to the operative position, and a control operable to release the brake following release of the clutch parts including a part on the nut, and a lever on the brake band engageable by the said part.

11. In a power take-off attachment for a tractor, a tubular support, a winding drum rotatable on the support, a tubular rotatable and longitudinally shiftable member extending through th e support, a stationary shaft extending through the member, means for rotating the member, a brake drum on the winding drum, a clutch part on the winding drum, a clutch part on the member cooperable with the first named clutch part, a

tor, a housing to be secured at the rear of the tractor, a substantially vertical drum above the housing, means on the housing for driving the drum, a, line wound on the drum and passing laterally therefrom, a leaf spring attached to the housing and projecting laterally therefrom, a sheave on the spring guiding the line forwardly, and means adjustably fixing the dead end of the line comprising a take-up spool on which the line is Wound, and releasable ratchet means normally preventing turning of the spool.

13. In a power take-olf attachment for a tractor, a housing to be attached to the tractor, an upwardly projecting tubular extension on the housing, a drum rotatably supported on the extension, a .driven member extending upwardly through the extension, a clutch at the upperend of the extension operable to transmit rotation from the driven member to the drum, and a brake at the upper end of the drum for controlling rotation of the drum.

14. In a power take-off attachment for a tractor, a housing to be attached to the tractor, an upwardly projecting tubular extension on the housing, a drum rotatably supported on the extension, a driven member extending upwardly through the extension, a clutch at the upper end of the extension operable to transmit rotation from the driven member to the drum, the clutch comprising cooperable relatively shiftable clutch parts associated with the drum and driven member, a fixed element and a nut threaded on the xed element to shift one clutch part relative to the other, a brake for controlling the drum, and means for governing the brake comprising a part on the nut and a part on the brake engageable by the last named part. o

HUGH ALLEN HUTCHINS. 

